The former 'Gavin & Stacey' star plays 'Britain's Got Talent' champion Paul Potts - the opera singer who won the first series of the TV talent show - and he is "very proud" of the comedy biopic.

He told The Observer Magazine: "[It is a] really, really uplifting positive film. I felt very proud of it when I watched it.

"And I feel like we might have made a really tender, uplifting story about a boy who refuses to give up."

The movie tells the story of the former shop assistant's rise to fame, and James admitted he wasn't immediately sold on the idea.

He added: "I was a bit, 'What sort of film is this going to be?' You know, is there going to be an actor playing Simon Cowell with a cigar in his mouth?"

In the end, the 35-year-old actor was convinced after a conversation with director David Frankel, who showed a complete dedication and love for the story.

James explained: "[He] left his kids in Miami to go to Port Talbot to make a film on a budget when he could have been spending $60 million shooting in New York.

"I asked him, 'Why did you want to do it?' And he said, 'Because the end is brilliant. And I know the end is brilliant because even a four-minute YouTube clip of this guy's audition makes people tingle, and 100 million people have watched it'.

"And he said, 'Imagine seeing that when you know everything this guy wet through. The absolute struggle it took to get there.' "